Operating mechanism for rotary slips



July 1s, 1963.v B. F. KELLEY 3,097,409

OPERATING MECHANISM FOR ROTARY SLIPS Filed Nov. 14, 1961 2 ShSebS-Sheei'l 1 July 16, 1963 B. F. KELLEY OPERATING MECRANISM FoR ROTARY sLIRs Filed Nov. 14. 1961 United States Patent O 3,097,409 GPERATING MECHANISM FOR ROTARY SLEPS Benjamin F. Kelley, c/a Ben F. Kelley Co., Inc., 18 S. Madison, rIulsa, Okla. Filed Nov. 14, 1961, Ser. No. 152,299 6 Claims. (Cl. 24-263) This invention relates to rotary `slip apparatus employed in well drilling and production operations for releasably supporting drill pipe or casing which is being run in or out of a well bore, and more particularly to operating mechanism by which pipe gripping slips are raised and lowered into and out of gripping engagement with the pipe in such well operations.

In the drilling and servicing of wells, such as oil and gas wells, it is customary to provide slip mechanism, which is operable to grippingly engage the string of drill pipe, casing or other pipe, which is being run in or removed from the well `to support the same while disconnecting or connecting in sections of pipe above the well head, and which may be released from the string to allow the same to be raised or lowered in the well. Slip mechanism for this purpose commonly includes a slip bowl located at the well head, which is formed with a downwardly tapering bore through which the pipe may be extended into or withdrawn from the well and tapered slips disposed in the bowl `about the pipe which may be lowered into wedging engagement with the pipe to grip the pipe or raised out of such gripping engagement.

Slip mechanism of this kind is usually provided with operating mechanism by which the slips may be raised and lowered in unison, while being held in substantially level horizontal arrangement relative to each other and also permitted to rotate as a unit about the axis of the pipe. Automatic slip mechanism of the kind with which this invention is concerned is disclosed in detail in my U.S. Patent Nos. 2,340,597, 2,594,446, and 2,829,617.

The present invention has for an important object the provision of rotary slip operating apparatus embodying improved linkage mechanism for lifting and lowering the slips.

Another object of the invention is to provide rotary slip lifting apparatus embodying linkage mechanism having means for holding the mechanism in assembled condition in the event of breakage, vwhereby the falling of pieces of the mechanism into the well bore is prevented.

A further object of the invention is the provision in slip lifting mechanism for .rotary slip apparatus of a slip supporting and lifting link which is of simple design and rugged construction and which is designed to reduce wear -on the bearings thereof and which is easily replaceable.

Another object of the invention is the provision of pressure fluid operated rotary slip lifting mechanism embodying means for limiting upward movement of the slips to prevent accidental movement of the slips entirely out of the slip bowl.

A further object of the invention is to provide rotary slip lifting apparatus embodying extensible land retractable pressure fluid operated mechanism which is extensible to lift the slips to release the same and retractable to lower the ysli-ps to pipe-engaging position and including means for preventing over-extension of such mechanism.

The above and other important objects and advantages of the invention will be apparent from the following detailed description and explanation of the construction and mode of operation of the same, reference being had to the annexed drawings, wherein- FIGURE l is a side elevational View, partly in crosssection, of a rotary Vslip operating mechanism, in accordance with the invention, showing the position of the 3,097,409l Patented July 16, 1963 ice mechanism with the slips in their lowered, pipe-engaging position;

FIGURE 2 is a view, similar to that of FIGURE l showing the position of the mechanism with the slips in their lifted, pipe-releasing position;

FIGURE 3 is a side elevational view of a portion of the slip lifting apparatus of the invention, on a greatly enlarged scale, showing the linkage mechanism in the position it occupies with the slips in released position;

FIGURE 4 is an end elevational view of the linkage mechanism as shown in FIGURE 3; and

FIGURE 5 is a `cross-sectional view, taken along the line 5 5 of FIGURE 3, looking in the direction indicated by the arrows.

Referring now to the drawings in greater detail, the rotary slip mechanism of the invention includes a slip bowl 10 of usual construction, which is supported in rotary table mechanism of conventional design, shown in dotted lines and generally designated by the letter T, mounted at the upper end of the well bore. The slip bowl has a laterally extending annular ilange 10a and -has a downwardly tapered conically shaped bore 12 and is adapted to be nonrotatably seated in the rotary table in position for the lowering into `the bowl of a conventionally circularly arranged set of pipe gripping slips of usual construction, such as the single slip shown at 14, which are of wedge shape and provided with serrated pipe-gripping faces for coaction with the bowl to grippingly engage the external surface of a well pipe P extending through the bore of the bowl, when the slips are lowered into the bowl and which may be lifted vertically in the bowl to release the slips from such gripping engagement.

Above the slip bowl, a support ring 16 is carried on a yoke 18 which is mounted in a horizontal position on the outer end of an arm -member 20. The latter is pivotally mounted lby means of lthe pivot pin 19 on a horizontal bracket 21 which is securely attached to a vertically disposed sleeve 22 slidable over the exterior of a hollow post 24 whose lower end is attached to a supporting structure such `as the rotary housing, as by means of a beam 26. Arm member 20 is secured against pivotal movement on bracket 21 by means of the holddown clamp 27 mounted on bracket 21 so as to embrace the inner end of the arm member and which is releasable to allow the yoke 18 with its suspended elements to be swung laterally out of registration with Ithe rotary table when the rotary slips are not in use. At its lower end the post 24 has an external annular end flange 28, which rests upon the upper face of a closure plate 30 closing the upper end of a cylinder 32 located Abeneath and in verticalalignment with the post and having an external annular flange 34 upon which the plate 3l) rests. The upper end 4of the sleeve 22 is closed as indicated at 36, as is also the lower end of the cylinder 32, as indicated at 38.

A piston 40 is slidably disposed in the cylinder 32 and is connected to a piston rod 42 which is slidably extended upwardly through the plate 30 into the bore `of the post 24 and centrally through the upper end of the sleeve 22, to which the -rod is securely attached, so that the sleeve will be moved vertically upon movement of the piston in the cylinder.

The closure plate 30 is securely clamped between the flanges 28 and 34` of the post 24 and cylinder 32, whereby these parts are formed into a unitary structure.

An opening 4-4 is provided in the plate 30 through which fluid under pressure may be introduced into and removed from the cylinder 32 above the piston 40 therein, and the cylinder has an -opening through the lower end 3S thereof through which such ud may ilow into and out of the cylinder beneath the piston through a pipe 46. Thus, 'by introduction of fluid under pressure into the cylinder beneath the piston, the piston may be moved upwardly to raise the sleeve 22 or such fluid may be introduced into the cylinder above the piston to cause downward movement of the sleeve. During upward movement of the piston uid is allowed to flow out through the opening 44 and upon downward movement of the piston iluid may iiow out through the pipe 46. The flow of iluid into the cylinder above and beneath the piston from a suitable source of pressure fluid and the outilow of fluid therefrom may be controlled by suitable valve means connected into the system in a conventional manner, such source and valve means not being shown in the drawings.

The linkage mechanism by which the slips 14 (only one shown) are `connected to the above described pressure fluid Vactuated lifting mechanism comprises a bell crank lever 48 for each slip, which is pivotally connected at one end to the upper portion of the slip and at the other end to a hinge arm 50, which is in turn pivotally connected to ange 10a of the slip bowl. The lever 48 is pivotally connected intermediate its ends to the support ring, as by means of a connecting link 52 which has one end pivotally secured to lever 48 and the other end pivotally secured to a bracket 53 appropriately mounted on ring 16.

The bell crank 48 is of integral construction `formed with elongated, spaced apart, parallel, beam-like, side portions connected together intermediate their ends by laterally extending portions such yas lthose shown at 54, 54. The beamlike portions of the lever 48 are formed with vertically disposed webs 56 having longitudinally extending rib portions S and 60 along one side thereof.

At each end of the bell crank, laterally thickened pairs of hub-like portions are provided, such as those shown at `62, 62 and 64, 64, the hub-like portions of each pair being formed with bores which .are aligned laterally of the bell crank for the insertion therein of pivot pins 66. A similar pair of laterally thickened, hub-like portions 68, 68 is also provided intermediate the ends of the bell crank, which are also formed with laterally aligned bores for the reception of a hinge pin 70.

Each of the hub-like portions of the bell crank 48 has a bore 72 therethrough which intersects the bore in which the pivot pin is inserted .and the pivot pins are each provided with laterally extending bores 74 near their ends which are positioned to be moved into registration with the bores 72 to permit the insertion of locking pins 76 into the registering bores to hold the pivot pins against rotation in the bell crank.

The hinge arm or anchoring link 50 is pivotally `anchored at its lower end to the slip bowl ange a, as by means of a pin 78 extending through spaced apart perforated ears 80 attached to the flange and through a perforation in the lower end portion yof the link. The link 50 is also perforated at its upper end which is inserted between the hub-like portions 64 of the bell crank 48 .and pivotally connected thereto by a pin 74 upon which the link is rotatable. Y

The connecting link 52 is perforated at its lower end and is inserted between the intermediate hub-like portions 68 of the bell crank and pivotally connected thereto by another pin 70, the connecting link being also perforated at its upper end for insertion between spaced apart perforated ears 84 depending from the support ring 16 to which the link is pivotally attached by -a p-in 86. Each of the slips 14 has at its upper end a perforated ear 87 which may be extended between the hub-portions 62 of one of the bell cranks 48 and pivotally secured thereto by a pin 66 to pivotally support the slip in a depending pos1t1on from one end of the bell crank. The links 50 and 52 may be provided with suitable grease littings 82 by which lubricant may be supplied to the pivotal pins 74, 78 and 86.

It will be apparent that by the above described construction, the pivot pins are held stationary in the rhubportions tof the bell crank, thus substantially reducing the wear on the pins and crank. Moreover, in the event of accidental breakage of the pins 76 during operation of the mechanism, the parts will be securely held in assembled relation to prevent pieces from falling into the well bore. The provision of the Ithickened hub-portions 62, 64 and 68 on lthe bell crank and the formation of the crank with the vertically widened webs 56 and external longitudinal ribs 58 and 68 connecting the thickened hub-portions, results in a structure possessing greatly increased strength and resistance to breakage.

The invention also includes means lfor limiting upward movement of the sleeve 22 which may be adjusted to stop such upward movement at a location to prevent the accidental complete withdrawal of the slips from the slip bowl. For this purpose ta pair of spaced apart, upwardly extending, tubular, internally threaded lugs 88 are provided on the ilange 28 of the post 24 positioned externally of the sleeve 22. The lugs 88 are provided with screws 98 threaded into their upper ends and which pass through spaced apart perforations in a horizontally disposed stop plate 92. The screws 90 carry nuts 94 and 96 threaded thereon above and beneath the plate 92 by which the plate is securely clamped on the screws.

The sleeve 22 has an external lug 98 which is located below the stop plate 92, and which is positioned for engagement therewith upon upward movement of the sleeve to limit such upward movement. It will be appa-rent that by adjusting the vertical position of the plate 92 on the screws 90 the `distance which the sleeve 22 may move upwardly may be regulated to lallow the slips 14 to have limited upward movement in the bowl 10 but to prevent the accidental movement of the slips entirely out of the bowl.

In operating the above `described Islip lifting mechanism, fluid under pressure, such as air, is admitted into the lower end of the cylinder 32 through pipe 46 while allowing the outiiow of fluid from the cylinder above the piston 40 through the `opening 44, whereupon the piston and piston rod 42 will be moved upwardly to move the sleeve 22 upwardly. Such upward movement of the sleeve results in upward movement of the yoke 18 and ring 16 to exert lan upward pull on the connecting links 52 to rock the bell cranks 48 upwardly `from the position of FIGURE l to that of FIGURE 2, whereby the slips 14 will be lifted upwardly to release the pipe P. Upon such upward movement of the sleeve 22, the lug 98 will be moved into engagement with the lower face of the stop plate 92 While the slips are still extending downwardly with their lower `ends in the bowl so that the slips are out of gripping engagement with the pipe P and positioned to move downwardly in the bowl upon lowering of the sleeve.

When the pipe P has been raised or lowered to the desired extent, -uid under pressure may be introduced into the cylinder 32 through `opening 44 while allowing the outflow of fluid through the pipe 46 to move the piston 40 and th-e sleeve 22 downwardly, thus again lowering the slips in the bowl into gripping engagement with the pipe.

In the event that the lbell crank or any of the pins 66 or 70 should become broken during `operation of the equipment, the parts will be securely held together because of the locking of the pins in the hub-portions by the locking pins 76, so that the yfalling of loose parts into the well will be prevented.

It will thus 'be seen that the invention provides rotary slip actuating mechanism which is Aof strong and durable construction and in 4which means is embodied for preventing damage due to breakage of the linkage mechanism.

The invention is disclosed herein in connection with a particular embodiment of the same, but it will be understood that this is intended by way of illustration only, and that various modicati-ons can be made in the construction and arrangement of the parts within the spirit of the invention and the scope of the appended claims.

Having thus clearly shown and described the invention, what is claimed as new and desired to Ksecure by Letters Patent is- 1. In rotary slip mechanism, the combination with a slip bowl through which a pipe may be extended centrally and slips movably disposed in the bowl for movement to positions for coaction with the bowl and pipe to grippingly engage the pipe `and to releasing positions out of ysuch engagement of means `for moving the slips `from one to the other of said positions, said means including an annular lifting ring vertically `spaced from the top of the `slip bowl and reciprocable relative thereto, linkage mechanism operatively connecting the lifting ring to each of said slips, said linkage mechanism comprising a bell crank lever having one end pivotally connected to one of said slips, a hinge link pivotally connecting the opposite end of said lever to the slipbowl, a connecting link pivotally connecting an intermediate portion of the bell crank lever to said lifting ring, said bell crank lever having spaced apart parallel side portions rigidly connected together intermediate their ends and each formed with a laterally thickened hub portion at each `end and laterally thickened hub portions located intermediate the ends of said side portions, each of said hub portions having a bore therethrough and the bores of the hub portions on `one of said side portions being axially aligned with the bores of the corresponding hub portions on the other of said side portions, pins extending between the side portions and into the bores of corresponding ones of Said hub portions, `said pins providing said pivoted connections between said lever and the other elements of lsaid linkage mechanism, means connecting the hub portions and pins to hold the pins against rotational and axial movement in the bores, a cylinder, piston means reciprocable in the cylinder, means for introducing pressure iluid into the cylinder for reciprocating the piston therein, means forming a connection between the piston and lifting ring to cause the lifting ring to move with the piston, and means for limiting the movement of the piston in the slip-releasing direction.

2. In rotary slip mechanism, the combination with a slip bowl through which a pipe may be extended centrally and slips movably disposed in the bowl for movement to positions for coaction with Ithe bowl and pipe to grippingly engage the pipe and to releasing positions out of such engagement, of means for moving the slips from one to the other of said positions, said means including an annular lifting ring vertically spaced from the top of the slip bowl and reciprocable relative thereto and linkage mechanism operatively connecting the lifting ring to each of said slips, said linkage mechanism comprising a bellcrank lever having one end pivotally connected to one of said slips, a hinge link pivotally connecting the opposite end of said lever to the slip bowl, and a connecting link pivotally connecting an intermediate portion of the bell-crank lever to said lifting ring, said bellcrank lever having `spaced apart, parallel side portions rigidly connected together intermediate their ends and each formed with a later-ally thickened hub portion at each end and laterally thickened hub portion located intermediate the ends of said side portions, each of said hub portions having a bore therethrough and .the bores of the hub portions on one of said side portions being Iaxially aligned with the bores of the corresponding hub portions on the other of said side portions, pins extending between the side portions and into the bore of corresponding ones of said hub portions, said pins providing said pivoted connections between said lever and the other elements of said linkage mechanism, and means connecting the hub portions and pins to hold the pins against rotational and axial movement in the bores.

3. in rotary slip mechanism, the combination with a slip bowl through which a pipe may be extended centrally and slips movably disposed in the bowl for movement to positions for coaction with the bowl and pipe to grippingly engage the pipe and to releasing positions out of such engagement, of means for moving the slips from one to the other of said positions, said means including an annular lifting ring vertically spaced from the top of the slip bowl and reciprocable relative thereto and linkage mechanism operatively connecting the lifting ring to each of said slips, said linkage mechanism comprising a bell crank lever having one end pivotally connected to one of said slips, a hinge link pivotally connecting the opposite end of said lever to the slip bowl, and a connecting link pivotally connecting an intermediate portion of the bell-crank lever to said lifting ring, said bell-crank lever having spaced [apart web portions disposed in parallel planes rigidly connected together intermediate their ends and each formed with longitudinally spaced, laterally thickened hub portions each having a bore therethrough, the bores of the hub portions on one web being aligned axially with the bores of the corresponding ones of the hubs on the other web, pins extending between the webs and into the aligned bores, said pins providing said pivoted connections between said lever and the other elements of said linkage mechanism, and means connecting the lpins to the hub portions to hold the pins against rotational and axial movement in the bores.

4. In rotary slip mechanism, the combination with a slip bowl through which a pipe may be extended cen- Itrally and slips movably disposed in the bowl for movement to positions for coaction with the bowl and pipe to grippingly engage the pipe and to releasing positions out of such engagement, of means for moving the slips from one to the other of said positions, said means inclnding an annular lifting ring vertically spaced from the top of the slip bowl and reciprocable relative thereto and linkage mechanism operatively connecting the lifting ring to each of said slips, said linkage mechanism comprising a bell-crank lever having one end pivotally connected to one of said slips, a hinge link pivotally connecting the opposite end of said lever to the slip bowl, and a connecting link pivotally connecting an intermediate portion of the bell-crank lever to said lifting ring, said bell-crank lever having spaced apart, parallel side portions rigidly connected together intermediate their ends and each formed with a web portion disposed in a plane parallel to the web portion of the other side portion rand longitudinally spaced thickened hub portions extending laterally from each side of the web portion and each having a bore therethrough which is in axial alignment with the bore of a corresponding hub portion of the other web portion, pins extending between the web portions and into the aligned bores, said pins providing said pivoted connections between said lever and the other elements of said linkage mechanism, and means connecting the pins to the hubs to hold the pins against rotational and axial movement in the bores.

5. In rotary slip mechanism, the combination with a slip bowl through which a pipe may be extended centrally and slips movably disposed in the bowl for movement to positions for coaction with the bowl and pipe to grippingly engage the pipe and to releasing positions out of such engagement, of means for moving the slips from one to the other of said positions, said means including an annular lifting ring vertically spaced from the top of the slip bowl and reciprocable relative thereto and linkage mechanism operatively connecting the lifting ring to each of said slips, said linkage mechanism comprising a bell-crank lever having one end pivotally connected to one of said slips, a hinge link pivotally connecting the opposite end of said lever to the slip bowl, and a connecting link pivotally connecting an intermediate portion of the bell-crank lever to said lifting ring, said bell-crank lever having spaced apart, parallel side portions rigidly connected together intermediate their ends and each formed with a web portion disposed in a plane parallel to the web portion of the other side portion and longitudinally spaced laterally thickened hub portions on the web portions each having a bore therethrough which is in axial alignment with the bore of a corresponding hub portion of the other web portion, said side portions having longitudinally extending external ribs on said web portions extending between the hub portions thereof, pins extending between the web portions and into the aligned bores, said pins providing said pivoted connections between said lever and the other elements of said linkage mechanism, and means connecting the pins to the hub portions to hold the pins against rotational and axial movement in the bores.

6. In rotary slip mechanism, the combination with a slip bowl through which a pipe may be extended centrally and slips movably disposed in the bowl for movement to positions for coaction with the bowl and pipe to grippingly engage the pipe and to releasing positions out of such engagement, of means for moving the slips from Vone to the other of said positions, said means including an annular lifting ring vertically spaced from the top of the slip bowl and reciprocable relative thereto and linkage mechanism operatively connecting the lifting ring to each of Said slips, said linkage mechanism comprising a bell-crank lever having one end pivotally connected to one of said slips, a hinge link pivotally is connecting the opposite end of said lever to the slip bowl, and a connecting link pivotally connecting an intermediate portion of the bell-crank lever to said lifting ring, said bell-crank lever having spaced apart, parallel vside portions rigidly connected together intermediate their ends and each formed with longitudinally spaced laterally thickened hub portions each having an axial bore which is in axial alignment with the bore of a corresponding hub portion of the other side portion and a bore intersecting the axial bore thereof, bearing pins extending between the side portions and into the aligned bores and each having bores therethrough which are disposed in axial alignment with the intersecting bores of the hubs, said bearing pins providing said -pivoted connections between said lever and the other elements of said linkage mechanism, and locking pins extending through the bores of the bearing pins and said intersecting bores to hold the bearing pins against rotational and axial movement in the hub portions.

References Cited in the le of this patent UNITED STATES PATENTS 2,575,356 Mullinix Nov. 20, 1951 2,636,241 Liljestrand Apr. 28, 1953 2,641,816 Liljestrand June 16, 1953 2,814,461 Martin Nov. 26, 1957 2,969,702 Cornish et al. Jan. 31, 1961 

3. IN ROTARY SLIP MECHANISM, THE COMBINATION WITH A SLIP BOWL THROUGH WHICH A PIPE MAY BE EXTENDED CENTRALLY AND SLIPS MOVABLY DISPOSED IN THE BOWL FOR MOVEMENT TO POSITIONS FOR COACTION WITH THE BOWL AND PIPE TO GRIPPINGLY ENGAGE THE PIPE AND TO RELEASING POSITIONS OUT OF SUCH ENGAGEMENT, OF MEANS FOR MOVING THE SLIPS FROM ONE TO THE OTHER OFF SAID POSITIONS, SAID MEANS INCLUDING AN ANNULAR LIFTING RING VERTICALLY SPACED FROM THE TOP OF THE SLIP BOWL AND RECIPROCABLE RELATIVE THERETO AND LINKAGE MECHANISM OPERATIVELY CONNECTING THE LIFTING RING TO EACH OF SAID SLIPS, SAID LINKAGE MECHANISM COMPRISING A BELL CRANK LEVER HAVING ONE END PIVOTALLY CONNECTED TO ONE OF SAID SLIPS, A HINGE LINK PIVOTALLY CONNECTING THE OPPOSITE END OF SAID LEVER TO THE SLIP BOWL, AND A CONNECTING LINK PIVOTALLY CONNECTING AN INTERMEDIATE PORTION OF THE BELL-CRANK LEVER TO SAID LIFTING RING, SAID BELL-CRANK LEVER HAVING SPACED APART WEB PORTIONS DISPOSED IN PARALLEL PLANES RIGIDLY CONNECTED TOGETHER INTERMEDIATE THEIR ENDS AND EACH FORMED WITH LONGITUDINALLY SPACED, LATERALLY THICKENED HUB PORTIONS EACH HAVING A BORE THERETHROUGH, THE BORES OF THE HUB PORTIONS ON ONE WEB BEING ALIGNED AXIALLY WITH THE BORES OF THE CORRESPONDING ONES OF THE HUBS ON THE OTHER WEB, PINS EXTENDING BETWEEN THE WEBS AND INTO THE ALIGNED BORES, SAID PINS PROVIDING SAID PIVOTED CONNECTIONS BETWEEN SAID LEVER AND THE OTHER ELEMENTS OF SAID LINKAGE MECHANISM, AND MEANS CONNECTING THE PINS TO THE HUB PORTIONS TO HOLD THE PINS AGAINST ROTATIONAL AND AXIAL MOVEMENT IN THE BORES. 